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Arnaud de Zordo-Banliat Dr. Kevin Grollier Dr. Nicolas Vanthuyne Dr. Sébastien Floquet Dr. Thierry Billard Guillaume Dagousset Bruce Pégot Emmanuel Magnier 《Angewandte Chemie (International ed. in English)》2023,62(12):e202300951
A selective access to perfluoroalkyl selenoxides, via Oxone® as oxidant or to selenones by using a Polyoxometalate-based Ionic Liquid (POM-IL) as a catalyst for the oxidation step is described. The reaction works with various perfluoralkyl chains and substituents with satisfactory to excellent yields. A two-step one-pot reaction from selenocyanates was performed to gain access to perfluoroalkyl selenoxides. The previously unknown perfluoroalkyl selenoximines family was also prepared with good yields. Having unlocked two strategies for the synthesis of fluoroalkylated SeIV and SeVI compounds, we then evaluated the Hansch-Leo lipophilicity parameters of these groups. Finally, asymmetric aryl perfluoroalkyl selenoximines were resolved to determine their absolute configurations. 相似文献
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Dr. Yu Zhu Siyue Liu Johnny Zigmond Kevin M. Kaltenbronn Prof. Dr. Kendall J. Blumer Prof. Dr. Kevin D. Moeller 《European journal of organic chemistry》2023,26(20):e202300365
YM-254890 and FR900359 are potent and selective inhibitors of the Gq/11-signaling pathway. As such, they have been attractive targets for both synthesis and biological studies. Yet in spite of this effort, a versatile synthetic approach to the molecules that allows for the rapid construction of a variety of non-natural and labelled analogs and an increase in the amount of those analogs available remains elusive. We report here a convergent building block approach to the molecules that can solve this challenge. 相似文献
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María del Carmen Fernández-Ramírez Kevin Kan-Shing Ng Margarita Menéndez Douglas V. Laurents Rubén Hervás Mariano Carrión-Vázquez 《Angewandte Chemie (International ed. in English)》2023,62(19):e202209252
Understanding early amyloidogenesis is key to rationally develop therapeutic strategies. Tau protein forms well-characterized pathological deposits but its aggregation mechanism is still poorly understood. Using single-molecule force spectroscopy based on a mechanical protection strategy, we studied the conformational landscape of the monomeric tau repeat domain (tau-RD244-368). We found two sets of conformational states, whose frequency is influenced by mutations and the chemical context. While pathological mutations Δ280K and P301L and a pro-amyloidogenic milieu favored expanded conformations and destabilized local structures, an anti-amyloidogenic environment promoted a compact ensemble, including a conformer whose topology might mask two amyloidogenic segments. Our results reveal that to initiate aggregation, monomeric tau-RD244-368 decreases its polymorphism adopting expanded conformations. This could account for the distinct structures found in vitro and across tauopathies. 相似文献
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We report in situ spectroscopic measurements monitoring the adsorption of a series of carboxylate surfactants onto the surface of the semisoluble, ionic solid fluorite (CaF2). We employ the surface-specific technique, vibrational sum-frequency spectroscopy (VSFS), to examine the effect that surfactant adsorption has on the bonding interactions and orientation of interfacial water molecules through the alteration of the electric properties in the interfacial region. In addition, we report on the chain length and headgroup dependence of the formation of hydrophobic self-assembled monolayers on the surface of the solid phase. Differences in chain length and headgroup functionality lead to large changes in the adsorption behavior and structuring of the monolayers formed and the interactions of interfacial water molecules with these monolayers. Fundamental studies such as these are essential for understanding the mechanisms involved in the surfactant adsorption process, information that is important for industrially relevant processes such as mineral ore flotation, waste processing, and petroleum recovery. 相似文献